Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P04626 (erbB-2)
 5,251 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Abnormalities of the type 1 growth factor receptor family have been implicated in the pathogenesis of pancreatic cancer. There is evidence for a potential autocrine loop involving overexpression of the epidermal growth factor (EGF) receptor and its ligands, as well as overexpression of the erbB-2 receptor. A third member of this receptor family, erbB-3, has recently been recognized and found to be abnormally expressed in some types of human cancer. In this study we show that overexpression of the erbB-3 protein occurs very frequently in carcinoma of the exocrine pancreas and also in chronic pancreatitis. We found no evidence of amplification or rearrangement of the erbB-3 gene by Southern blot analysis of DNA from pancreatic cancer cells lines.
 ...
PMID:The erbB-3 gene in human pancreatic cancer. 136 25

The clinical significance of the measurement of c-erbB-2 oncogene product was evaluated. The subjects consisted of 404 patients, including 248 with cancer of the digestive organs and 128 with benign digestive diseases. Serum c-erbB-2 protein levels were measured by sandwich immunoenzyme assay. The positive rates of c-erbB-2 protein, at a cut-off value of 17.0 U/ml, were, for cancers: hepatocellular carcinoma 61.6%, biliary tract cancer 54.8%, pancreatic cancer 25.0%, esophageal cancer 33.3%, gastric cancer 16.9%, and colorectal cancer 5.0%. For benign digestive diseases, the rates were: liver cirrhosis 63.3%, chronic hepatitis 43.2%, acute hepatitis 42.9%, other liver diseases 42.8%, cholelithiasis 30.0%, and chronic pancreatitis 0%. Serum c-erbB-2 protein levels were significantly correlated with the markers of hepatic functional reserve, the indocyanine green retention rate and the hepaplastin test. These findings suggest that serum c-erbB-2 protein levels are greatly influenced by liver dysfunction and that their clinical usefulness as a serum tumor marker is questionable.
 ...
PMID:Serum levels of c-erbB-2 protein in digestive diseases. 752 80

The expression of oncoprotein, tumor suppressor gene, cellular proliferation and differentiation markers were studied in 64 malignant and benign pancreatic tumors, adjacent and distant to the tumor duct epithelium. Activity of these markers was compared to 16 cases of chronic pancreatitis. Tumor suppressor gene p53 and transforming growth factor alpha were overexpressed in the majority of malignant tumors. The expression of c-erbB-2 oncoprotein and cellular proliferation marker Ki67 was less common in malignant lesions, but was absent in the benign cases. The positive staining of all markers in ductal epithelium outside of the tumor, particularly in pancreatic duct carcinoma, suggest the ductal histogenesis of this malignancy. The presence of c-erbB-2 and Ki67 in malignant lesions only suggest their possible use in the differentiation of pancreatic malignancies and chronic pancreatitis.
 ...
PMID:Expression of p53 tumor suppressor gene, oncoprotein c-erbB-2, cellular proliferation and differentiation in malignant and benign pancreatic lesions. 784 27

The bad prognosis of exocrine pancreas carcinoma manifests itself by a high incidence of recidivation, early metastasis formation and a low 5-year survival rate of 1-2% on an average has not essentially been improved in recent times although progress is evident in diagnosis as well as in surgical, radiological and cytostatic therapy. The unfavourable course of illnesses is due to the symptomless early phase rather than the existing diagnostic potential. Thus, a recording, standardization and definition of pancreatic duct atypias is a necessity for optimizing the pattern of examinations. Topographically, the structure of pancreatic parenchyma may be classified by 1) interlobular ducts; 2) intralobular ducts; 3) intercalated ducts; 4) centroacinar cells, and 5) acinar cells. Based on this matrix, entities of varying diagnostic relevance may be derived, i.e. 1) orthological histiomorphological tissue formations; 2) hyperplastic epithelial changes; 3) metaplastic epithelial formations; and 4) atypical hyperplasias. Beyond this, there are numerous indications of a redifferentiation of numerous pancreatic cell types, primarily of acinar cells. The close relationships between ductal and acinar cells may be subsumed as a terminal ductulo-acinar intercalated duct complex. Against the background of chronic pancreatitis and corresponding length of history (< 6.5 years), cancer may develop in up to 16% of cases. On the molecularbiological level, point mutations of the K-ras gene, a mutation or deletion of the p53 suppressor gene and an excess production of the c-erbB-2 protooncogene are found in a great number of pancreatic carcinomas.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Lesions of the pancreatic duct epithelium and histogenesis of exocrine pancreatic carcinomas]. 794 29

The epidermal growth factor (EGF) receptor is a transmembrane protein that binds EGF and transforming growth factor alpha (TGF alpha), and that stimulates phospholipase C gamma 1 (PLC gamma 1) activity. In this study the role of the EGF receptor in chronic pancreatitis was studied. By immunohistochemistry, the EGF receptor, TGF alpha, and PLC gamma 1 were found to be expressed at high concentrations in pancreatic ductal and acinar cells from chronic pancreatitis patients. Northern blot analysis showed that, by comparison with normal controls, 19 of 27 chronic pancreatitis tissues exhibited a 5.7-fold increase in EGF receptor mRNA concentrations, and 20 of 27 chronic pancreatitis tissues exhibited a sixfold increase in TGF alpha mRNA concentrations. In situ hybridisation confirmed that overexpression occurred in ductal and acinar cells, and showed that both mRNA moieties colocalised with their respective proteins. These findings suggest that TGF alpha may act through autocrine and paracrine mechanisms to excessively activate the overexpressed EGF receptor in the two major cell types of the exocrine pancreas, thereby contributing to the pathobiology of this disorder.
 ...
PMID:Chronic pancreatitis is associated with increased concentrations of epidermal growth factor receptor, transforming growth factor alpha, and phospholipase C gamma. 795 7

Pancreatic cancer is the fifth leading cause of cancer death in the United States, and despite improvements in the results of surgical treatment for this disease, little impact has been made upon overall mortality. New advances in treatment will depend upon improved adjuvant therapy, early diagnosis, and a better understanding of tumor biology. This article summarizes the results of molecular genetic studies in pancreatic cancer and their potential clinical significance. Familial predisposition to pancreatic cancer, cytogenic studies, DNA ploidy analysis, and examination of specific oncogenes and tumor suppressor genes are reviewed. The most frequent mutations detected have been in the K-ras oncogene, which occur in 80% of pancreatic cancers. These mutations do not correlate with tumor stage or survival, but can be useful in differentiating pancreatic exocrine from endocrine tumors and chronic pancreatitis. Mutations in the p53 gene occur in approximately 50% of tumors, and appear to be an independent prognostic factor for patient survival. Mutations in the CDKN2 gene are frequently seen in sporadic pancreatic cancers, and have been implicated in cases of familial pancreatic cancer. The significance of mutations in APC, MCC, DCC, c-erbB-2, RB-1, and mismatch repair genes in the genesis of pancreatic cancer is less clear.
 ...
PMID:The molecular genetics of pancreatic cancer. 936 57

Pancreatic intraepithelial neoplasia is only partially defined. Any attempt to establish the diagnostic criteria of early pancreatic carcinoma has been unsuccessful so far. In the present study we investigate expression of HER-2/neu in hyperplastic pancreatic duct epithelium. Material included resected pancreatic tissue obtained from 13 patients with pancreatic carcinoma, 11 with chronic pancreatitis, and 11 patients operated on for other reasons (gastric cancer, carcinoma of papilla Vateri). Hyperplasia of pancreatic duct epithelium was scored as: 1. flat mucosal hyperplasia FH, 2. papillary hyperplasia PH, 3. atypical papillary hyperplasia APH, 4. carcinoma in situ CIS. Immunohistochemical expression of HER-2/neu was studied with the biotin-streptavidin method. Results were scored as: 1+ barely perceptible light membranous rimming, 2+ light to moderate rimming, 3+ moderate to strong rimming. Expression of HER-2/neu paralleled with the hyperplasia grading, in most cases being negative in normal duct epithelium, weak in flat hyperplasia, and moderate to strong in atypical papillary hyperplasia and carcinoma in situ. In conclusion, HER-2/neu expression could be used as an additional marker of hyperplasia, dysplasia and atypia of pancreatic ductal and ductular epithelium in the process of pancreatic epithelial neoplasia. This could be especially useful in the cytological diagnosis of pancreatic intraepithelial neoplasia.
 ...
PMID:HER-2/Neu expression as a progression marker in pancreatic intraepithelial neoplasia. 979 11

The erbB-4 gene encodes a detected receptor protein that possesses intrinsic tyrosine kinase activity and belongs to the family of the epidermal growth factor receptor (EGFR); erbB-4 is stimulated by the heregulins and betacellulin, which enables this receptor to form heterodimers with erbB-2, a prerequisite for erbB-2 activation. Because the expression of erbB-4 mRNA is generally low in the pancreas, quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was used to determine the erbB-4 levels in human normal and cancerous pancreatic tissue. Our results show that the mRNA expression of this receptor is 6-fold decreased in the non-metastatic stages of pancreatic cancer when compared to tumors with lymph node or distant metastases or to the normal pancreas. In addition, immunohistochemistry demonstrated that in the normal pancreas, the erbB-4 antigen was predominantly present in the cell membrane and cytoplasm of the ductal and acinar cells and at a much lower level, in islet cells. In pancreatic cancer, 61 of 75 samples exhibited weak to moderate immunoreactivity for erbB-4 in the tumor cells. Moreover, in the peri-tumorous region with chronic pancreatitis-like morphological changes, there was weak-to-moderate erbB-4 immunostaining in small ductules and degenerating acinar cells. Uni- and multivariate survival analyses using as variables age, sex, stage of cancer, histo-pathological grading, and erbB-4 immunoreactivity, revealed a significant effect for stage of cancer (p < 0.01) whereby the risk of dying was 2.3 times higher in patients with metastases than in patients without. However, the level of erbB-4 immunoreactivity in pancreatic cancer cells had no influence on patient survival.
 ...
PMID:ErbB-4 mRNA expression is decreased in non-metastatic pancreatic cancer. 998 27

The pathobiology of precursor lesions leading to invasive pancreatic adenocarcinoma remains a controversial area, but knowledge of the mechanisms of tumorigenesis may lead to possibly earlier detection, prevention, and treatment in the future. We hypothesize that ductal hyperplasia and dysplasia of the pancreas represent precursor lesions and are part of a continuous developmental spectrum evolving into ductal adenocarcinoma of the pancreas. To further define this sequence, we studied the immunohistochemical markers HER-2/neu, K-ras, and p53 in 15 adenocarcinomas and 15 nonmalignant specimens of the pancreas. The 15 nonmalignant specimens of the pancreas included both normal pancreas and chronic pancreatitis. Overall, HER-2/neu was positive in normal ducts, ductal hyperplasia, dysplasia, and carcinoma cells in 0 of 30, 11 of 20 (55%), 10 of 15 (67%), and 12 of 15 (80%), respectively, with progressive increase in the intensity of staining; p53 was positive in 1 of 30 (3%), 0 of 20, 3 of 15 (20%), and 13 of 15 (80%), respectively, and K-ras was positive in 1 of 30 (3%), 6 of 20 (30%), 11 of 15 (73%), and 8 of 15% (53%), respectively. These data support the hypothesis that ductal hyperplasia and dysplasia of the pancreas represent precursor lesions, and, in a fashion similar to that in colorectal tumorigenesis, pancreatic cancer seems to accumulate progressive genetic alterations.
 ...
PMID:Immunohistochemical evaluation of K-ras, p53, and HER-2/neu expression in hyperplastic, dysplastic, and carcinomatous lesions of the pancreas: evidence for multistep carcinogenesis. 1002 38

Pancreatic cancer belongs to the neoplasms which are characterised by increasing morbidity and mortality. Five-year survival rates of about 0.4% are the norm, and little has changed in the last 70 years. Important etiological factors are age, sex, diet, tobacco smoking, alcohol abuse, occupation and chemical exposure, hereditary chronic pancreatitis, and previous surgery (cholecystectomy and gastrectomy). The majority of exocrine tumours of the pancreas are malignant and 80-90% of them comprise ductal adenocarcinomas. The development and growth of pancreatic carcinoma appears to be caused by a progressive accumulation of multiple genetic abnormalities. This includes oncogene (K-ras) activation, loss of tumour-suppressor p53 gene function and overexpression of growth factors and their ligands. The morphological background for the development of pancreatic carcinoma is ductal epithelial hyperplasia. Current molecular studies have resulted in the identification of cell clones exhibiting the same genetic alterations (K-ras and p53 mutations) as in infiltrating pancreatic carcinoma. Pancreatic intraepithelial neoplasia is only partially defined. The purpose of our study was to evaluate Ki-67 proliferative index and HER-2/neu gene expression in pancreatic intraepithelial proliferative lesions as a sign of increasing epithelial proliferation and dysplasia. Additionally we made an attempt to apply morphometry in demarcating between intraepithelial proliferations of "reactive" type and proliferations with tendency towards progression to cancer. Another aim of the study was to evaluate the expression of bcl-2 and p53 genes in various types of pancreatic intraepithelial proliferations and in pancreatic cancer and to answer the question whether they interact in the process of pancreatic intraepithelial neoplasia. We have also undertaken investigations aiming at determination of the CD44s gene and its v6 isoform expression in intraductal and invasive pancreatic carcinoma, attempting to correlate this expression with the p53 gene mutations. The results of our study indicate that intraductal pancreatic proliferations form a group of heterogeneous lesions possessing different proliferative activity of cells, karyometric features and HER-2/neu, bcl-2 and p53 genes expression. The precancerous lesion in the pancreas may be atypical papillary hyperplasia, which is similar to intraductal carcinoma with respect to the proliferative activity of cells and HER-2/neu, bcl-2 and p53 expression. Pancreatic carcinoma is characterised by high p53, CD44s and CD44v6 expression and low bcl-2 expression. CD44 and p53 genes expression is independent and between bcl-2 and p53 expression there is an inverse correlation. The p53 and CD44v6 expression is the higher the lower is the histological grade of the pancreatic carcinoma.
 ...
PMID:[Morphologic, morphometric and immunohistochemical studies on pancreatic intraductal hyperplasia and infiltrating carcinoma]. 1090 69


1 2 Next >>